Uv-B radiation: Anatomical, physiological and biochemical changi glasshouse - grown ornamental plants

Abstract

Three glasshouse-grown ornamental plants, viz. Monstera deliciosa, Calathea lindeniana and Syngonium podoph were treated with UV-B radiation at a level of 0.8 mW cm-2 for about 7 h daily for six days. Changes in leaf anatomy, phenolic compounds, photosynthetic pigments and chlorophyll fluorescence (Fv/Fm ratio) were studied. Leaves of the three plants showed changes in their inner structure. Phenolic compounds such as caumarin, flavonol, flavone and anthocyanin(s) were also accumulated in response to the UV-B treatment. Plants showed variability in accumulation of type of phenolic compounds in response to the treatment. Chlorophyll a, b and xanthophylls (violaxanthin, lutein, etc.) decreased to a greater extent while beta-carotene remains unaffected. Photosynthetic efficiency of the plants changed to varying degrees in response to the UV-B treatment. We suggest that these anatomical and biochemical changes in plants take place in order to adapt/survive in the high UV-B environment.